00933706

Component

https://doi.org/10.3141/1801-08

http://scholar.google.com...nson&publication_year=2002

Retroreflective materials for traffic control devices are designed to return light from a vehicle's headlamps back to the driver. Recent advances in material technology have created prismatic retroreflective sheeting. This type of material does not have the predictability in its retroreflective performance of the older, glass-bead material. The American Society for Testing and Materials (ASTM) recently recognized three new types of prismatic material for traffic control devices. The on-road performance of these new material types was examined through the use of computer simulation of sign luminance. Inputs to the computer model included vehicle dimensions, headlamp illumination data, material retroreflectivity data, sign placement, and roadway geometry. A variety of sign positions and roadway types was included to illustrate the similarities and differences among the three new types of material. The ranking of the three materials in terms of sign-luminance performance depends on the roadway configuration and the viewing distance. ASTM Type VII is shown to be comparable to Type VIII at long distances with small entrance angles but superior to Type VIII and IX in large entrance-angle situations. ASTM Type IX is shown to have higher luminance at shorter distances associated with sign-legibility distance ranges. Engineers and specifiers are encouraged to evaluate on-road sign performance at night before making material choices.

This paper appears in Transportation Research Record No. 1801, Traffic Control Devices, Visibility, and Rail-Highway Grade Crossings 2002.

English

p. 61-72

2002

Transportation Research Record

0309077273

Figures (11) ; References (15) ; Tables (5)

Computer models; Distance; Geometric design; Highway design; Legibility; Location; Luminance; Materials; Performance tests; Retroreflectivity; Sign sheeting; Simulation; Specifications

ASTM International

Geotechnology; Highways; Materials; Operations and Traffic Management; I35: Miscellaneous Materials; I73: Traffic Control

TRIS, TRB

Nov 12 2002 12:00AM

• ASSESSMENT AND IMPROVEMENT OF SAFETY AT FINNISH RAILWAY-ROAD GRADE CROSSINGS
• COMPUTATIONAL VISION MODEL TO ASSESS WORK-ZONE CONSPICUITY
• DRIVER UNDERSTANDING OF SIMULTANEOUS TRAFFIC SIGNAL INDICATIONS IN PROTECTED LEFT TURNS
• EVALUATION OF CLEARVIEW ON FREEWAY GUIDE SIGNS WITH MICROPRISMATIC SHEETING
• FLUORESCENT SIGN COLORS FOR INCIDENT MANAGEMENT TRAILBLAZING: EVALUATION OF ASSIGNMENTS IN "MANUAL ON UNIFORM TRAFFIC CONTROL DEVICES"
• FREEWAY GUIDE SIGN DESIGN WITH DRIVING SIMULATOR FOR CENTRAL ARTERY-TUNNEL: BOSTON, MASSACHUSETTS
• MODEL OF OVERHEAD-SIGN LUMINANCE NEEDED FOR LEGIBILITY
• PHOTO ENFORCEMENT AT HIGHWAY-RAIL GRADE CROSSINGS IN THE UNITED STATES: JULY 2000-JULY 2001
• ROUNDABOUT WARRANTS: PROPOSED FRAMEWORK FOR FUTURE DEVELOPMENT